Novel facultative anaerobic acidotolerant Telmatospirillum siberiense gen. nov. sp. nov. isolated from mesotrophic fen

Three facultative anaerobic acidotolerant Gram-negative motile spirilla strains designated 26-4b1, 26-2 and K-1 were isolated from mesotrophic Siberian fen as a component of methanogenic consortia. The isolates were found to grow chemoorganotrophically on several organic acids and glucose under anoxic and low oxygen pressure in the dark, tolerant up to 5kPa of oxygen. At low oxygen supply, faint autotrophic growth on the H(2):CO(2) mixture was also observed. All three isolates were able to fix N(2). Major cellular fatty acids were 18:1 omega7c, 17:0 cyclopropane and 16:0. Phylogenetic analyses of the 16S rRNA gene sequences revealed that they formed a deep branch within the family Rhodospirillaceae of the Alphaproteobacteria with the highest similarity of 90.9-92.5% with members of genera Phaeospirillum and Magnetospirillum. Phylogenetic study of nifH (nitrogenase) and cbbL (RuBisCO) amino acid sequence identities confirmed that the new isolates represent a novel group. Based on the phylogenetic analyses and distinct phenotypic characteristics, we are of the opinion that strains 26-4b1, 26-2 and K-1 represent a new species of a novel genus for which the name Telmatospirillum siberiense gen. nov. sp. nov. is proposed.     

A study of the thermophilic ribosomal protein S7 binding to the truncated S12-S7 intercistronic region provides more insight into the mechanism of regulation of the str operon of E. coli(1).

A study of the ability of His6-tagged ribosomal protein S7 of Thermus thermophilus to interact with the truncated S12-S7 intercistronic region of str mRNA of Escherichia coli has been described. A minimal S7 binding mRNA fragment is a part of the composite hairpin, with the termination codon of the S12 cistron on one side and the initiation codon of the next S7 cistron on the other. It has a length in the range of 63-103 nucleotides. The 63 nucleotide mRNA fragment, which corresponds to a putative S7 binding site, binds very poorly with S7. Tight RNA structure models, which behave as integral systems and link the S7 binding site with the translational regulation region of the hairpin, are suggested. This observation provides more insight into the mechanism of S7-directed autogenous control of translational coupling of str mRNA.     

Analysis of the Alu insertion polymorphism in urban and rural populations of Siberia]

Polymorphic Alu-repeat loci of human genome are commonly used as effective genetic markers in population and evolution studies. In this work, the data on genetic structure of two Russian populations from Siberia obtained via analysis of five polymorphic Alu repeats are presented. The urban population was characterized by a slightly higher level of genetic diversity compared to the rural population. The value of genetic differentiation coefficient for the populations studied was 0.57%, pointing to the absence of genetic subdivision within the urban and rural populations. Phylogenetic analysis of these populations, together with literature data, shows that, with respect to the markers examined, the gene pool structure of Russian population is similar to that of other Caucasoid populations.     

A system for screening natural immunosuppressors

Criteria for directed screening of antibiotics with immunosuppressive action were defined. The first stage included screening of cultures producing antiaspergillous antibiotics. At the second stage, the antibiotics whose antifungal activity decreases in the presence of insulin (at the background of calcium salts) and erythromycin and increases in the presence of verapamil were selected. The screening of antibiotic-producing cultures among 123 strains of mycelial fungi and 181 strains of actinomycetes resulted in isolation of 3 fungal cultures and 2 actinomycetes which produced antibiotics corresponding to cyclosporine A as evidenced by thin-layer and high performance liquid chromatographies.     

Efficacy of bacteriophages in complex treatment of patients with burn wounds]

Results of clinical and laboratory evaluation of the treatment with pyobacteriophage in tablets of the patients with burn wounds are presented. It was shown that phagotherapy provided more rapid cure of pyoseptic complications, temperature normalization, wounds purification and lower lethality Bacteriological analysis of wound secretions revealed that after the treatment staphylococci and streptococci were cultured 2 times rarely, Proteus spp. Were isolated 1.5 times rarely, E. coli was not isolated. The amount of positive haemocultures also diminished. Investigation of immunologic status demonstrated statistically significant normalization of immunity on cell level. Phagocytosis level didn't change while in control group (without bacteriophage use) it became lower. Antibody level enhanced but less extensively than in control group. The results of trial demonstrates positive effect of phagotherapy use at the patients with burns.     

Isolation and identification of an antibiotic from culture 8-86]

An antibiotic complex was isolated from culture 8-86 referred to Bacillus. The complex consisted of components 8-86A and 8-86B active against gram-negative organisms. By its physico-chemical properties such as IR and UV spectra, amino acid composition, specific rotation and fatty acid composition component 8-86B was shown to be close to polymyxin F.     

Systematic review and meta-analysis: rapid diagnostic tests versus placental histology, microscopy and PCR for malaria in pregnant women

Background

To prepare field sites for malaria vaccine trials, it is important to determine baseline antibody and T cell responses to candidate malaria vaccine antigens. Assessing T cell responses is especially challenging, given genetic restriction, low responses observed in endemic areas, their variability over time, potential suppression by parasitaemia and the intrinsic variability of the assays.

Methods

In Part A of this study, antibody titres were measured in adults from urban and rural communities in Ghana to recombinant Plasmodium falciparum CSP, SSP2/TRAP, LSA1, EXP1, MSP1, MSP3 and EBA175 by ELISA, and to sporozoites and infected erythrocytes by IFA. Positive ELISA responses were determined using two methods. T cell responses to defined CD8 or CD4 T cell epitopes from CSP, SSP2/TRAP, LSA1 and EXP1 were measured by ex vivo IFN-γ ELISpot assays using HLA-matched Class I- and DR-restricted synthetic peptides. In Part B, the reproducibility of the ELISpot assay to CSP and AMA1 was measured by repeating assays of individual samples using peptide pools and low, medium or high stringency criteria for defining positive responses, and by comparing samples collected two weeks apart.

Results

In Part A, positive antibody responses varied widely from 17%-100%, according to the antigen and statistical method, with blood stage antigens showing more frequent and higher magnitude responses. ELISA titres were higher in rural subjects, while IFA titres and the frequencies and magnitudes of ex vivo ELISpot activities were similar in both communities. DR-restricted peptides showed stronger responses than Class I-restricted peptides. In Part B, the most stringent statistical criteria gave the fewest, and the least stringent the most positive responses, with reproducibility slightly higher using the least stringent method when assays were repeated. Results varied significantly between the two-week time-points for many participants.

Conclusions

All participants were positive for at least one malaria protein by ELISA, with results dependent on the criteria for positivity. Likewise, ELISpot responses varied among participants, but were relatively reproducible by the three methods tested, especially the least stringent, when assays were repeated. However, results often differed between samples taken two weeks apart, indicating significant biological variability over short intervals.     

Comparative phylogeography of two crow species: jungle crow Corvus macrorhynchos and carrion crow Corvus corone

The jungle crow Corvus macrorhynchos Wagler, 1827, and the carrion crow Corvus corone L., 1758, are two closely related species with similar ecological requirements that occupy wide distribution ranges in the Palearctic. We studied patterns of their genetic variation by using sequences of the mitochondrial cytochrome b gene. Corvus macrorhynchos demonstrates a low level of variation and differentiation throughout its range, except for a highly diverged population of Cheju Island (Korea). The haplotype network shows two haplogroups. The island group comprises populations of Sakhalin, Hokkaido, Honshu, and Kyushu, while the haplotypes of Taiwan and Ryukyu Islands proved to be closer to the mainland group, which also includes populations from the Primorye, Khabarovsk, Amur, and Magadan regions in the Russian Far East. This pattern allowed us to develop a phylogeographic hypothesis regarding the two modes of settling of the island populations. Concerning C. corone, the presence of two distinct haplogroups was confirmed within the range of C. c. orientalis. Both haplogroups are found within the same populations in Kamchatka and North Sakhalin, which implies secondary contacts there. Populations of C. corone are found to be rather stable in the western parts of its range, while in the Far East populations experienced recent growth, as was observed for C. macrorhynchos in general. The two species appear to have passed through different evolutionary scenarios.